When her friend returns from Africa with a strange skin condition, a doctor suspects a pathogen from out of the past.

Ay-yi-yeee! the pain running down the back of my arm—like a jolt of current traveling a frayed electric cord—caught me off guard. I had never felt a sensation quite like it. On the other hand: Why not? I had just finished a grueling week of hospital consults. My middle-aged frame was simply complaining in a new way, right? I probably just needed rest. “Move over, Ollie,” I mumbled. My dozing spaniel made space on the living room couch and I soon drifted off, pain forgotte...

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